How is the Church apostolic? “The Church is apostolic because she is founded on the apostles, in three ways:

- she was and remains built on ‘the foundation of the Apostles,’ the witnesses chosen and sent on mission by Christ himself;

- with the help of the Spirit dwelling in her, the Church keeps and hands on the teaching, the ‘good deposit,’ the salutary words she has heard from the apostles;

- she continues to be taught, sanctified, and guided by the apostles until Christ’s return, through their successors in pastoral office: the college of bishops, ‘assisted by priests, in union with the successor of Peter, the Church’s supreme pastor’: You are the eternal Shepherd who never leaves his flock untended. Through the apostles you watch over us and protect us always. You made them shepherds of the flock to share in the work of your Son…” [1]

What was the mission of the apostles? If the Church is apostolic, it is good to look first at what the first apostles were charged to do. “From the beginning of his [Jesus’] ministry, he ‘called to him those whom he desired;…And he appointed twelve, whom also he named apostles, to be with him, and to be sent out to preach.’ From then on, they would also be his ‘emissaries’. In them, Christ continues his own mission: ‘As the Father has sent me, even so I send you.’ The Apostles’ ministry is the continuation of his mission; Jesus said to the Twelve: ‘he who receives you receives me.’” [2]

How is the Church still “apostolic” since the apostles are all dead? When the apostles were either martyred or died, the Church still continued Christ’s mission. “In order that the mission entrusted to them might be continued after their death, [the apostles] consigned, by will and testament, as it were, to their immediate collaborators the duty of completing and consolidating the work they had begun, urging them to tend to the whole flock, in which the Holy Spirit had appointed them to shepherd the Church of God. They accordingly designated such men and then made the ruling that likewise on their death other proven men should take over their ministry.” [3] By passing down the mission in the nature, the apostles set up what we now know as apostolic succession. Today the bishops are the successors of the apostles and carry out Christ’s mission in the one true Church.

How else is the Church apostolic? “The whole Church is apostolic, in that she remains, through the successors of St. Peter and the other apostles, in communion of faith and life with her origin: and in that she is ‘sent out’ into the whole world. All members of the Church share in this mission, though in various ways. ‘The Christian vacation is, of its nature, a vocation to the apostolate as well.’ Indeed, we call an apostolate ‘every activity of the Mystical Body’ that aims ‘to spread the Kingdom of Christ over all the earth.’” [4]

“Christ, sent by the Father, is the source of the Church’s whole apostolate’; thus the fruitfulness of apostolate for ordained ministers as well as for lay people clearly depends on their vital union with Christ. In keeping with their vocations, the demands of the times and the various gifts of the Holy Spirit, the apostolate assumes the most varied forms. But charity, drawn from the Eucharist above all, is always ‘as it were, the soul of the whole apostolate.’” [5]

In conclusion, “The Church is ultimately one, holy, catholic, and apostolic in her deepest and ultimate identity, because it is in her that ‘the Kingdom of heaven,’ the ‘Reign of God,’ already exists and will be fulfilled at the end of time. The kingdom has come in the person of Christ and grows mysteriously in the hearts of those incorporated into him, until its full eschatological manifestation. Then all those he has redeemed and made ‘holy and blameless before him in love,’ will be gathered together as the one People of God, the ‘Bride of the Lamb,’ ‘the holy city Jerusalem coming down out of heaven from God, having the glory of God.’ For ‘the wall of the city had twelve foundations, and on them the twelve names of the twelve apostles of the Lamb.’” [6]